Answer:
P-value is greater than the significance level, we fail to reject null hypothesis.
Explanation:
Here,
Sample size = n = 120
Sample proportion = p = 0.6500
Population Proportion = 
= 0.5
Level of significance = α = 0.02
<u />
<u>Step 1:
</u>
: p = 0.5
: p < 0.5 (Left tailed test)
<u></u>
<u>Step 2:
</u>
The critical vale is = 2.0537
<u></u>
<u>Step 3: </u>
The test statistic is,
z = 
<u>Step 5:
</u>
Conclusion using critical value: Since the test statistic value is greater than the critical value, we fail to reject null hypothesis.
<u>Step 6: </u>
Conclusion using P-value: Since the P-value is greater than the significance level, we fail to reject the null hypothesis.
Is the total value income earned in a year exactly
Answer:
$0.013
0.010724
Explanation:
Given that :
Mean, m = 36500
Standard deviation, s = 5000
Refund of $1 per 100 mile short of 30,000 miles
A.) Expected cost of the promotion :
P(X < 30,000)
Using the Zscore relation :
Zscore = (x - m) / s
Zscore = (30000 - 36500) / 5000
= - 6500 / 5000
= - 1.3
100 miles = $1
1.3 / 100 = $0.013
b. What is the probability that Grear will refund more than $50 for a tire?
100 miles = $1
$50 = (100 * 50) = 5000 miles
Hence, more than $50 means x < (30000 - 5000) = x < 25000 miles
P(x < 25000) :
(25000 - 36500) / 5000
-11500 / 5000
= - 2.3
P(z < - 2.3) = 0.010724 (Z probability calculator)
